In order to inquire into the therapeutic effects of Xiao Shi Xiong Huang San (the Nitrum and Realgar Powder), one of the Dunhuang Prescription, on angina pectoris due to coronary heart disease (APCHD), the authors have treated 61 cases of APCHD by externally applying paste of the powder on Zhiyang (GV 9), with another 30 cases of APCHD treated with the nitroglycerin paste on Zhiyang as the controls. The results showed that the total effective rate was 82% and markedly effective rate 31.2% in the treatment group (the Paste of Nitrum and Realgar Powder), and the total effective rate was 46.6% and markedly effective rate 23.2% in the control group (the nitroglycerin paste). The difference in therapeutic effects between the two groups was very significant (P<0.01), indicating that the therapeutic effect of the former was significantly superior to that of the latter.